The conventional gear shift lever for an automatic transmission of an automotive vehicle has a "Park" position. It is common practice to place the gear shift lever in the "Park" position when turning off the engine. For reasons of safety, it is recommended that the operator depress the brake pedal and at least lightly apply the brakes when starting the engine and shifting out of "Park". What is needed is a simple and effective mechanical system for locking the gear shift lever in the "Park" position and for releasing the lock on the gear shift lever to enable shifting out of "Park" by depressing the brake pedal.
In accordance with the present invention, a gear shift lever retainer is mounted on the gear shift lever for movement to an advanced position in which it is engageable with a "Park" detent to prevent movement of the gear shift lever out of "Park". A lock is movable toward and away from a locking position in which it locks the retainer in the advanced position. A mechanical connection is provided between the brake pedal arm and the lock for moving the lock away from its locking position when the brake pedal arm is moved toward brake-applying position, thereby releasing the lever retainer so that it may be retracted and the gear shift lever shifted out of "Park".
The mechanical connection preferably comprises a cable connected to one end of a pivotally mounted cable retractor. The cable retractor retracts the cable in response to movement of the brake pedal arm toward its brake-applying position. A spring is provided for the cable retractor. The spring, when the brake pedal is in the brake-release position, causes the retractor to advance the cable and move the lock to its locking position.
One object of this invention is to provide a releasable lock mechanism as described above, having the foregoing features and capabilities.
Another object is to provide a releasable lock mechanism which is mechanical in structure, and composed of a relatively few simple parts, is rugged and durable in use, and is capable of being inexpensively and readily manufactured and assembled.
These and other objects, features and advantages of the invention will become more apparent as the following description proceeds, especially when considered with the accompanying drawings.